论文部分内容阅读
GNSS Timing is the process for users to obtain the UTC time from the satellite navigation signal.At present each GNSS has the timing function,but timing performance characterization of different navigation systems is not unifiied as well as the published data not comparable,which makes the users great inconvenience.Accrording to the users using characteristics,the paper proposes the conception and method to test the bias between UTC broadcasted by the satellites and actual UTC,which studies the timing testing methods of single satellite and multiple satellites,and referring to the timing performance of GPS,GLONASS and BDS we develop the integrated testing and evaluation experiments.The result shows GPS timing error is better than 20ns,and GLONASS timing performance is less than GPS with timing error relatively higher fluctuation; Compared with GPS and GLONASS timing evaluation of BDS has still a certain distance that sometimes the maximum timing error can be up to 120ns,thus from the users perspective the UTC precision obtained by the BeiDou satellites is less than GPS and GLONASS.